Pesticidal phosphorous-containing imino oxazolidines

ABSTRACT

Compounds corresponding to the formula WHEREIN X and Y are independently oxygen or sulfur, R1 is lower alkyl, lower alkoxy, lower alkylthio, R2 is lower alkyl, lower alkoxy, lower alkylthio, chloro lower alkyl, carbethoxy methylthio, allylthio, chloro-phenylthio, nitrobenzyloxy, phenyl or substituted phenoxy in which said substituents are nitro, cyano, methylthio, chloro or tert.-butyl; R3 is lower alkyl, benzyl, phenyl, lower alkoxyalkyl, alkenyl, chloroalkenyl or 2propynyl; IN WHICH R4 is hydrogen, lower alkyl, cyclohexyl or vinyl, R5, R6 and R7 are independently hydrogen or lower alkyl; provided that when Q is -CH2CH2CH2- then R3 is other than benzyl. The above-mentioned compounds are biologically effective as pesticides, especially against insects and acarids, and as herbicides. Representative compounds are: 2-(N-(O,Odimethylphosphonothiono)-imino)-3-ethyl-5-methyl-1,3-oxazolidine, 2-(N-(0,0-diethylphosphonothiono)-imino)-3-ethyl-5-methyl-1,3oxazolidine, 2-(N-(0,S-dimethylphosphonothiolo)-imino)-3-ethyl-5methyl-1,3-oxazolidine, 2-(diethylthiophosphinoimino)-3-methyl oxazolidine, 2-(0,0-dimethylthiophosphorylimino)-3-methyl thiazolidine and 2-(O,O-dimethylthiophos-phoryl-imino)-3-allylperhydro-1,3-oxazine.

United States Patent [191 Gaughan 111 3,714,176 [451 Jan. 30, 1973 54] PESTICI'DAL PHOSPHOROUS- CONTAINING 1M 1N0 OXAZOLIDINES [75] Inventor: Edmund J. Gaughan, Kensing'ton,

Calif.

[73] Assignee: Stuaffer Chemical Company, Newv York, N. Y.

[22] Filed: March 23, 1970 21 Appl. No.: 22,039

Related Us. Application Data [63] Continuation-in-part of Ser. No. 705,017, Feb. 13, 1968, abandoned, which is a continuation-in-part of Ser. No. 673,993, Oct. 9, 1967, abandoned.

[52] -U.S. Cl ..260/307 F, 260/243 R, 260/244 R, 260/306.7,424/246, 424/248, 424/270,

Primary Examiner-Alex Mazel Assistant Examiner-R. V. Rush Attorney-Daniel C. Block, Edwin H. Baker and Albert J. Adamcik [57] ABSTRACT Compounds corresponding-to the formula l -N=CN-Rs Rg 'Y-Q wherein X and Y are independently oxygen or sulfur, R is lower alkyl, loweralkoxy, lower alkylthio,'R is lower alkyl, lower alkoxy, lower alkylthio, chloro lower alkyl, carbethoxy methylthio, allylthio, chlorophenylthio, nitrobenzyloxy, phenyl or substituted phenoxy in which said substituents are nitro, cyano, methylthio, chloro or tert.-butyl; R is lower alkyl, benzyl, phenyl, lower alkoxyalkyl, alkenyl, chloroalkenyl or 2-propynyl;

Ilia s 7 Q is (]J? or CH2CHCH in which R is hydrogen, lower alkyl, cyclohexyl or vinyl, R R and R are independently hydrogen or lower alkyl; provided that when Q is CH CH CH then R is other than benzyl. The above-mentioned 28 Claims, No Drawings PESTICIDAL PHOSPHOROUS-CONTAINING IMINO OXAZOLIDINES This application is a continuation-in-part of US. application Ser. No. 705,017, filed Feb. 13, 1968, now abandoned which in turn is a continuation-in-part of US. application Ser. No. 673,993, filed Oct. 9, 1967 now abandoned.

The present invention is concerned with a novel group of phosphoryl, thionophosphoryl, phosphonyl, thionophosphonyl, phosphinyl and thionophosphinyl imino oxazolidines, thiazolidines and perhydrooxazines, their method of preparation, and their use as pesticides especially effective against insects, acarids and as herbicides.

' The novel compounds are represented by the general formula wherein X and Y are independently oxygen or sulfur; R is loweralkyl, lower alkoxy, lower alkylthio; R is lower alkyl, lower alkoxy, lower alkylthio, chloro lower alkyl, carbethoxy-methylthio, allylthio, chlorophenylthio, nitrobenzyloxy, phenyl or substituted phenoxy in which said substituents are nitro, cyano, methylthio, chloro or tert.-butyl; R is lower alkyl, benzyl, phenyl, lower alkoxyalkyl, alkenyl, chloroalkenyl or 2-propynyl;

in which R is hydrogen, lower alkyl, cyclohexyl or vinyl, R R and R are independently hydrogen or lower alkyl. Provided that when Q is Cl-l Cl-l CH then R is other than benzyl.

The lower alkyl radicals which are suitable for R R R R R R and R are the straight and branched chain aliphatic radicals having from one to six carbon atoms and include, for example, methyl, ethyl, propyl, isopropyl, hexyl and the like. The lower alkoxy radicals for R, and R contain from one to six carbon atoms; the lower alkylthio radical for R contains from one to six carbon atoms; and the alkyl in chloro lower alkyl for R contains from one to three carbon atoms. In the lower alkoxyalkyl radical for R the alkoxy and alkyl portions thereof contain from one to three carbon atoms, for example, methoxyethyl, ethoxymethyl, ethoxyethyl, propoxypropyl and the like.

As a consequence of the special geometry of the compounds of this invention, the ring structure and restricted rotation within this structure, the possibility exists for geometric isomerism. Cis-trans isomerism is very frequently encountered in substituted ring structures of this type. It is recognized that the trans isomers are usually more stable than the corresponding cis isomers. Both stereoisomeric forms are believed to exist for the majority of the compounds described herein when possible. The compounds of the present invention are not limited to any specific geometric isomer configuration. In several instances, as seen below, both stereo isomers have been isolated and characterized. The physical properties of cis and trans isomers are usually quite similar and separation of both from a mixture by techniques such as fractional distallation or crystallization is not always possible. At the same time many of the compounds, due to the several possible asymmetric centers present in the molecule, have the possibility for optical stereoisomerism as well as the geometric isomerism, discussed above. This phenomenon is understood and recognized by those skilled in the art. The designations D" and L" found in Table l are used herein to indicate the configuration of the optically pure amino acids from which the compounds were made. No reference to the absolute or relative configurations of the final product is expressed or implied. To those skilled in the art, it is reasonable that such optical stereoisomerism is retained in the final product, and, therefore, the compounds prepared from optically pure starting materials will have a portion of their structures rich in the same absolute configuration.

The compounds herein described can be prepared by several "various methods. In one general method, the oxazolidines of the present invention are prepared by reacting the appropriate organo substituted phosphorus chloride with an alkali metal thiocyanate using acetone or acetonitrile as solvent. The isothiocyanate thereby produced is then reacted with the appropriate beta-hydroxy amine to give a thio urea which in the presence of mercuric oxide undergoes cyclicization with the loss of the elements of hydrogen sulfide and yields the desired phosphoryl, thiophosphoryl, phosphonyl, thiophosphonyl, phosphinyl or thiophosphinyl imino oxazolidine. The desired product is isolated by thin layer chromatography using methods well known to those skilled in the art.

The necessary starting imino oxazolidines of the instant invention can be prepared by the general method which begins with the reaction between an epoxide and an appropriate primary amine to give the corresponding amino alcohol. The resulting amino alcohol is then allowed to react with cyanogen bromide in the presence of a caustic such as sodium hydroxide to yield the corresponding 2-iminol,3-oxazolidine. The oxazolidine is then phosphorylated with an appropriate phosphoryl halide in the presence of sodium hydroxide. When a substituted phosphorothiono halidate is used as the phosphorylating agent, the product obtained is a phosphorothiono imino-l,3-oxazolidine. The resulting thiono compound can be rearranged to the, thiolo isomer by reaction with an alkyl iodide. The resulting compound is then 2-[O,S(di-substituted phosphorothiolo)imino1- l ,3-oxazolidine.

The preparation of phosphorodithio imino oxazolidines is readily accomplished by reacting the appropriate imino oxazolidine with a phosphorothiodichloridate to give a 2-[N(chloro-O- substituted-phosphorothiono)imino] oxazolidine. This intermediate is then reacted with a thiol-containing compound in the presence of caustic to yield the desired 2 -[N-(O,S-dl-Sllb$tllllt6d phosphorodithio)imino]-l ,3-oxazolidine.

The thiazolidines of the instant invention also are prepared according to the following general description of the synthetic procedure. Compounds of the form base lides. The products from this reaction have the general is obtained after dissolving the imino salt (2) in water and adding one equivalent, or more, of strong base (e.g., sodium hydroxide solution).

Either the imino salt (2) with two molar equivalents of base as acid acceptor or the free imine base (3) in molar excess or with one molar equivalent of another is phosphorylated using an alkoxy chlorothionophosphate (-phosphonate) in an inert solvent. This reaction is exothermic and the reaction temperature is held below 45 C by cooling. Bases which can be used as acid acceptors are sodium hydroxide, potassium carbonate, potassium hydrogen carbonate or tertiary amines such astriethylamine. Suitable solvents are acetone, methylene chloride, benzene or heterogeneous mixtures such as benzene/water. The final product isolated has the general structure wherein R, is lower alkyl.

The thionophosphor.(-phosphon) amides (4) are rearranged to thiolophosphor- (thiolophosphon-) amides (5) by dissolving them in an inert solvent (e.g.,

benzene, benzene/hexane) and refluxing with alkyl iodide (e.g., methyl iodide, ethyl iodide), or by refluxing them directly in the alkyl iodide. The products are purified by evaporating the solvent and alkyl iodide reagent, redissolving the crude product in a non-polar solvent such as benzene to precipitate the polar, solid by-product' usually accompanying the rearrangement. The benzene solution is filtered and the solvent removed to give the final product which can be further purified by recystallization or chromatography. The products have the general thiolo' structure (5).

wherein R A is lower alkyl.

The preparation of the 1,3-perhydrooxazines is carried out by reacting an appropriate substituted amine with ethyl acrylate to produce a B-amino ester. The B amino ester is reduced with lithium aluminum hydride to the 3-substituted-amino alkanol. The amino alkanol is reacted with cyanogen bromide (BrCN) in the presence of a base, such as powdered sodium hydroxide to yield the corresponding cyanamide. Treatment of the B-hydroxyalkyl cyanamide with a further quantity of sodium hydroxide promotes ring-closure to the corresponding imino perhydrooxazine. The imino perhydrooxazine is phosphorylated with the appropriate phosphorus containing acidchloride in a solution, such as benzene, in the presence of an acid acceptor such as sodium hydroxide. When a thiono phosphorus compound is prepared, rearrangement of the thiono to the thiolophosphorus compound is accomplished by reaction with an alkyl iodide in an appropriate solvent, such as benzene-hexane solution.

The following specific examples are illustrative of general methods discussed herein above.

EXAMPLE 1 0111 -0 s cm,

Preparation of 2-[N-(0,0-diethylphosphonothiono)- imino1-3-ethyl-5-methyl-l ,3 -oxazolidine To a solution of 38.8 grams (0.4 mole) ofpotassium thiocyanate in 395 ml. of acetone containing 6 grams of pyridine is added 75.4 grams (0.4 mole) of diethyl chlorothiophosphate over a 2 hour period. The mixture is stirred another hour at room temperature, then at 45-50 C. for 45 minutes. It is filtered fromthe precipitate of potassium chloride and the solvent removed in vacuo. The residue is taken up in benzene and the insoluble material removed. The benzene is removed in vacuo and the product distilled twice, the second time through a Vigreux column. 5.3' grams (0.025 mole) of this product is dissolved in 42 ml. of benzene; 2.7g. (0.025 mole) of ethyl B hydroxypropylamine in 10 ml. of benzene is added over l5 minutes. After letting the mixture stand overnight, the solvent is removed in vacuo leaving a crystalline product. To a solution of 3.3. grams (0.011 mole) of the above product in 50 ml. of benzene is added 3.7 grams (0.0167 mole) of mercuric oxide. The mixture is stirred and refluxed for 3.5 hours. The mixture is filtered and the filtrate dried over magnesium sulfate. The benzene is removed in vacuo leaving a crudeviscous product. This product is taken up in 35 ml. of benzene and refluxed with 2.0 grams of mercuric oxide for another 5 hours. The mixture is again filtered, dried and the solvent removed. Pure 2-[N-(0,0-Diethylphosphonothiono')-imino]-3-ethyl-5-methyl-l ,3-oxazolidine is isolated from the crude product by thin layer chromatography, using solvent systems 90:10 chloroformcacetone v/v on silica gel. Instrumental analysis establishes the above structure and elemental analysis shows 43.18 percent C, 7.53 percent H, 9.82 percent N, 11.23 percent P, and 11.27 percent S as compared with theoretical values of 43.20 percent C, 7.55 percent H, 10.00 percent N, 11.10 percent P and l 1.40 percent S.

Another general method for the preparation of the O,S-phosphorylimino oxazolidines of the present invention consists of reacting the product resulting from the reaction of the appropriate 0,0-phosphorodithioic acid and cyanogen bromide in the presence of EXAMPLE 2 Preparation of 2-]N-(O,S- Dimethylphosphonothiolo)-iminol-3-ethyl-5-methyl- 1,3-oxazolidine To a solution of 79.0 grams (0.5 mole) of 0,0- dimethylphosphonodithioic acid in 100 ml. of benzene is added 50.5 grams (0.5 mole) of triethylamine at to 25 vC. A solution of 53 grams (0.5 mole) of cyanogen bromide in 75 ml. of benzene is then added over 1.5 hours at 15 C. The reaction mixture is then stirred two more hours at room temperature, during which time the precipitate of amine hydrobromide becomes thicker. The mixture is filtered and the benzene removed from the filtrate in vacuo. The product is distilled at 55-58C./0.751.0 mm. yielding 44.0 grams. 5.5 grams of this intermediate product is dissolved in 44 ml. of dry acetone and to the solution is added a solution of 3.1 grams of ethyl B-hydroxypropylamine in 15 ml. of acetone. The mixture warms to 32 during addition and is stirred for 1.5 hours. The acetone is removed in vacuo and the residue pumped out at 0.4 mm. for 1.5 hours, yielding 8 grams. Upon standing, the product partially crystallizes. After the crystals are removed, the mixture is placed in 30 ml. of water and the mixture is extracted twice with 80 ml. portions of chloroform. The extract is dried over magnesium sulfate, filtered, and the solvent removed in vacuo. The residual oil is pumped out at 1 mm. up to 55 C. It is then seeded with one of the spontaneously formed crystals removed above and allowed to stand until all of the second component has crystallized out. The mixture is then filtered and the oily filtrate subjected to thin layer chromatography using 90:10 chloroformzacetone v/v and 95:5 ethanolzwater v/v solvent systems on silica gel, giving pure 2-[N-(O,S- dimethylphosphonothiolo)-imino]-3-ethyl-5-methylabove structure and elemental analysis shows 12.30

percent P compared to 12.30 percent P theoretical.

Another general method for the preparation of the O,S-phosphoryl imino oxazolidines of the present invention consists of reacting the appropriate 0,0- thiophosphonylimino oxazolidine with the appropriate alkyl or alkenyl iodide to form the desired product, which is isolated by thin layer chromatography using methods well known to those skilled in the art. The fo'llowing example is illustrative of the above general method.

EXAMPLE 3 Preparation of Dimethylphosphorothiolo)-imino]-3-ethyl-5-methyll ,3-oxazolidine I A solution of 7.6g. (0.03 mole) of 2-[N-(0,0- dimethylphosphonothiono)-imino]-3-ethyl-5-methyl- 1,3-oxazolidine and 4.4g. (0.031 mole) of methyl iodide in a mixture of 25 ml. of hexane and 5 ml. of benzene is refluxed for 5 hours. The mixture is cooled and filtered and the solvent removed in vacuo.

EXAMPLE 4 Preparation of Diethylthiophosphinoisothiocyanatot hioate Potassium thiocyanate (65.6 g., 0.75 mole) and a trace of potassium iodide are place in 500 ml. of dry acetone and warmed to 45. Dicthylthiophosphinochloridothioate (78.3 g., 0.5 mole) is added dropwise at 45-50. A precipitate of potassium chloride appeared. The mixture is then refluxed for 15 minutes. It is cooled, filtered, and the solvent removed in vacuo. The residue is treated with water and the oil extracted with hexane. The extract is washed with sodium bicarbonate solution and with water, dried, and the solvent removed in vacuo. The residue is distilled twice in vacuo. The product has a boiling point of 79-80/.3 mm. Yield: 49.0 g. (55 percent of theory). lts 1R spectrum showed a band characteristic of the isothiocyanate group at 2,000-2,050 cm.

Preparation of N-Diethylthiophosphinyl-N'-Methyl- N-hydroxyethyl thiourea.

The above-mentioned thioate (26.9 g., 0.15 mole) is dissolved in ml. of benzene and a solution of N- methylethanolamine (12.0 g., 0.16 mole) added dropwise. The temperature increased to 33 during the addition. Stirring is continued 1 hour at room temperature, 1 hour at 65-70. The reaction mixture is filtered through Celite and evaporated in vacuo. Upon trituation with hexane, the residue solidified. It is recrystallized from benzene-hexane, and has a m.p. 6873. Yield: 23.4 g. (61 percent oftheory).

Preparation of 2-(Diethylthiophosphinoimino)-3- methyl oxazolidine The above-mentioned thiourea (15.6 g., 0.07 mole) dissolved in 150 ml. of benzene is stirred and refluxed with mercuric oxide (32.6 g., 0.15 mole) under a Dean- Stark trap until no-more water is given off (about 3 hours). Black mercuric sulfide appears. The mixture is cooled, filtered, and the filtrate dried over magnesium sulfate. Removal of the solvent left a yellow oil. n,, 1.5563. Yield: 7.8 g. (51 percent of theory).

EXAMPLE 5 Preparation of the Intermediate 2-lmino-3-ethyl-5- methyl-1,3-oxazolidine Ethylaminoisopropanol (20.6 g., 0.2 mole) is dissolved in 90 ml. of benzene and powdered sodium hydroxide (8.0g, .2 mole) added. This mixture is stirred and a solution of cyanogen bromide (21.2 g., 0.2 mole) in 50 ml. of benzene added at 5l5 C. A precipitate of sodium bromide appeared. The mixture 'is stirred two hours at room temperature, filtered and the solvent removed in vacuo. The residue is distilled through a Vigreux column b.p. 57-59/2 mm. There is obtained a yield of 17.7 g. (69.1 percent) of the title compound. The IR spectrum showed the expected bands.

Preparation of 2-(0,0-dirnethylthionophosphorylimino)-3-ethyl-5-methyl-l,3-oxazolidine Dimethyl chlorothiophosphate (16.1 g., 0.1 mole) is added dropwise at -25 to a well stirred mixture of the iminooxazolidine (13.4 g., 0.105 mole) and sodium hydroxide (4.2 g., 0.105-mole) in 100 ml. of benzene and ml. of water. The mixture is stirred another four hours, the layers separated, and the organic layer is washed and dried. Removal of the solvent left a crystalline residue which is recrystallized from ether. m.p. 68-7l. There is obtained a yield of 18.0 g. (71.4 percent) of the title compound. The IR spectrum showed the expected bands. The structure was also confirmed by its NMR spectrum.

Preparation of 2-(O,S-dimethylthiolophosphorylimino)-3-ethyl-5-methyl-l ,3- oxaz0lidine The thiono compound (200 g., 0.79 mole) and methyl iodide (124.1 g., 0.87 mole) are refluxed in a mixture of 396ml. of benzene and 598 ml. of hexane for three hours. The solvent is removed in vacuo and about one liter of dry benzene is added to the residue. The mixture is allowed to stand over night and filtered through diatomaceous earth filter-aid. The benzene is removed in vacuo and the residue, a viscous yellow oil, pumped out under high vacuum. There is obtained a yield of l88.4 g. (94.2 percent). IR and NMR spectra confirmed the assigned structure. The product was about 80 percent pure by quantitative T.L.C. A chromatographically p'ure sample isolated by preparative T.L.C. showed n l .51 72.

EXAMPLE 6 2-lmino-3- In a l-liter round bottom flask containing a magnetic stirring bar is dissolved l 10 g. (1.08 moles) 2-amino-2- thiazoline in 230 ml. absolute methanol. To this solution are then added 153 g. 1.08 moles) methyl iodide. The temperature of the exothermic reaction was held below the boiling point by immersing the flask in a cold water bath. Stirring at room temperature is continued over approximately .a hour period. Within this period, a copious amount of solid precipitates. The reaction mixture is cooled in the refrigerator and the solid filtered. Concentration of the filtrate gives an additional crop of product. After drying, a total of 220.9 g. of crude product is isolated, m.p. 149-l59 C. Recrystallization of this material gives 207.6 g. of long, colorless needles, mp. l60.5-l62 C. Yield: 79 percent of theory. (literature, m.p. l59-160, S. Gabriel, Ber.22, 1,146 (1889).

Preparation of the Intermediate: 2-lmino-3- methylthiazolioline C=NH The free imine is obtained by mixing 66.9 g. (0.274

moles) 2-imino-3-methylthiazolidine hydrogen iodide with 30 ml. water and adding, with cooling in anice bath, 40 ml. of 25 percent (w/w) sodium hydroxide solution. A pH of about 10 is reached. The resulting solution is extracted continuously with benzene for two days using a liquid-liquid extraction apparatus. The benzene solution is dried over anhydrous magnesium sulfate, filtered and the benzene is evaporated. The residue is distilled through a 10 cm. Vigreaux column. There is collected 21.2 g. of product, bp. 96-96.5 C/4.l torr. Yield: 67 percent of theory. [Literatu'rez bp. 1l9-1.20 C/20 torr., K.K. Kuz'mina, et al., Zh. Obshch. Khim., 32, 3,215 (1962.)]

EXAMPLE 7 2-(0,0-Dimethylthiophosphorylimino)-3- methylthiazolidine Into a 500 ml. four-neck round bottom flask provided with stirrer, thermometer and pressure equalizing funnel are placed 16.9 g. (0.0694 moles) 2-imino-3- methylthiazolidine hydrogen iodide, 100 ml. benzene and 22.2 g. (0.139 equivalents) of 25 percent (w/w) sodium hydroxide solution. This heterogeneous mixture is stirred vigorously as 11.2 g. (0.0694 moles) 0,0-dimethyl chlorothiophosphate dissolved in 30 ml. benzene are added dropwise. The reaction temperature rose slowly but did not exceed 30 C. After the addition of chlorothiophosphate, stirring at room temperature is continued for an additional two hours. The benzene layer is separated and the aqueous layer is extracted thrice with 20 ml. portions of benzene. The combined benzene fractions are dried over anhydrous magnesium sulfate, filtered and the benzene is evaporated. The residual solid is recrystallized from petroleum ether/benzene to yield 13.9 g. of colorless crystals, m.p. 89-93 C. Yield: 83 percent of theory. On further recrystallization, the metling point could be raised to 90-92.5 C.

Anal. calcd. for C l-l N O PS C, 29.99; H, 5.45; N, 11.66; S, 26.69. Found: C, 29.54; H, 5.53; N, 11.61, S, 26.51.

The infrared spectrum (KBr pellet) showed a strong band at 1,590 cm C=N-vibration), and strong bands at 1,040 cm, 1020 cm 780 cm (P-O-C stretch).

EXAMPLE 8 2-(0,0-Dimethylthiophosphorylimino)-3- methylthiazolidine.

A solution of 9.5 g. (0.082 moles) 2-imino-3-methylthiazolidine in 100 m1. benzene is treated with 13.1 g. (0.082 equivalents) 25 percent (w/w) sodium hydroxide solution. To the resulting mixture are added slowly 13.1 g. (0.082 moles) 0,0-dimethyl chlorothiophosphate in 30 ml. benzene. The reaction temperature is held below 30 C with the aid of a water bath. After drying the benzene layer and then evaporating the solvent, a colorless solid remained. Recrystallization from petroleum ether/benzene gave 15.8 g., m.p. 8891 C. Yield: 80 percent of theory. The infrared spectrum of this material is identical to the spectrum obtained from the procedure in Example 7, supra.

EXAMPLE 9 2-(O,S-Dimethylthiophosphorylimino)-3- methylthiazolidine (If/cm o=N-P SCH: N CH3 A mixture of 120.5 g. (0.500 moles) 2-(0,0-

dimethylthiophosphorylimino)-3-methylthiazolidine, 400 ml. benzene and 213 g. (1.50 moles) methyl iodide are refluxed for 80 minutes. Most of the methyl iodide and benzene are evaporated. The remaining pale yellow liquid is redissolved in 500 ml. benzene and allowed to remain in contact overnight. A small amount of colorless solid by-product precipitated during this period. The benzene solution is filtered and the solvent evaporated. Some 1 13.5 g. of a viscous, colorless oil remained. Yield: 94 percent theory. Anal. calcd for C,,H,;,N O PS,: C, 29.99; H, 5.45; N, 11.66; .mol. wt., 240.29. Found: C, 29.63; H, 5.76; N, l 1.62; mole wt. (mass spectroscopy), 240 (based upon 32 The infrared spectrum of this compound (liquid film) showed a strong band at 1,590 cm C=N- vibration), a band at 1,210 cm (P=O), and bands at 1,040 cm and 780 cm (P-O-C stretch).

EXAMPLE 10 Preparation of the Intermediate 2-[N-(chloro-O- ethyl-phosphorothiono)-imino l-3-ethyl-5-methyl-l ,3- oxazolidine 44.5 g. of phosphorothiodichloridate is dissolved in 300 ml. of anhydrous ethyl ether. To this mixture a solution of 64.0 g. 2-imino-3-ethyl-5-methyl-1,3-oxazolidine in 400 ml. anhydrous ethyl ether is added dropwise at 10 C. The reaction mixture is stirred at room temperature for 2 hours. After filtering the solvent is removed on a rotary evaporator. There is obtained 67.0 g. (Yield: percent of theory) n 1.5245.

Preparation of 2-[N-(O,S-Diethyl phosphorodithio)- imino1-3-ethyl-5-methyl-1 ,3-oxazolidine A solution of 11.0 g. 2-[N-(chloro-O- ethylphosphorothiono)-imino]-3-ethyl-5-methy1-1,3- oxazolidine in 50 ml. tetrahydrofuran was added to 3.1 g. of ethanethiol and 2.0 g. of powdered sodium hydroxide in ml. tetrahydrofuran at room temperature. The mixture is stirred for 2 hours at 50 C. The solution is dried with anhydrous MgSO filtered and the solvent removed on a rotary evaporator. There is obtained 11.0 g. (Yield: 92 percent of theory) of the title compound, n =l.5139.

EXAMPLE 1 1 Preparation of 2- N-[O-ethyl-S-(4-chlorophenyl)phosphorodithiono]-imino-3-ethyl-5-methyl-1,3-oxazolidine I A solution of 11.0 g. 2-[N-(chloro-O- ethylphosphorothiono)-iminol-3-ethyl-5-methyl-1,3- oxazolidine in 50 ml. of tetrahydrofuran is added to 7.2 g. p-chlorothiophenol and 2.0 g. powdered NaOH in 100 m1. tetrahydrofuran. The mixture is stirred for two hours at 50 C. The reaction mixture is dissolved in ethyl ether and washed twice with 100 ml. of 10 percent NaOH solution and once with 100 ml. of water. The ether layer is then dried over anhydrous MgSO, and the solvent removed on rotary evaporator. There is obtained 14.7 g. (Yield: 94 percent of theory) of the title compound n,, =1.5753.

2-[N-(chloro-S-methylphosphorothio)-imino]-3- ethyl-S-methyl-l,3-oxazolidine is prepared in the same manner as described for 2-[N-(chloro-O-ethyl phosphorothio)-iminol-3-ethyl-5-methyl-1,3-oxazolidine starting with S-methyl thiophosphorodichloridate.

EXAMPLE 1 2 52 percent of theory) of the title compound, n

It is noted that when optically pure materials are used to prepare'compounds within the scope of this invention, a variation in insecticidal activity is observed. The preparation of such compounds, believed to be rich in one optical isomer due to retention of configuration throughout the synthesis, is carried out by starting with an appropriate optically pure amino acid such as D- or L-alanine. The amino acid is then acylated with an appropriate acylating agent such as acetic anhydride to yield an N-acyl amino acid which is then reduced with lithium aluminum hydride to give a 2-substitutedamino alkanol. The amino alkanol is reacted with cyanogen bromide (BrCN) in the presence of a base,

such as powdered sodium hydroxide to yield the cor- .responding cyanamide. Treatment of the B-hydroxyalkyl cyanamide with a further quantity of sodium hydroxide promotes the ring-closure to the corresponding imino oxazolidine. The imino oxazolidine is phosphorylated with the appropriate phosphorus containing acid chloride in a solution, such as benzene, in the presence of an acid acceptor such as sodium hydroxide, When a thionophosphorus compound is prepared, rearrangement to the thiolophosphorus compound is accomplished by reaction with an alkyl iodide in an appropriate solvent, such as benzenehexane solution.

The above general procedure is illustrated by the following specific preparations:

EXAMPLE 13 Preparation of the Intermediate: N-Acetyl-D- Alanine D-Alanine (25.0 g., 0.281 moles) is added to 100 ml. of water and then cooled in an ice bath while being rapidly stirred. Potassium hydroxide (185 g. of 85 percent KOH) in 50 ml. of water is added slowly, resulting in a clear solution. To this solution 28.6 g. of acetic anhydride is added with vigorous stirring, and the mixture stirred for 1 hour at room temperature. The resulting clear solution is acidified with 23.4 ml. of concentrated hydrochloric acid, poured into an evaporating dish, and the solvent allowed to evaporate. The concentrate is placed on a rotary evaporator and further concentrated until a viscous semi-solid is obtained which is then thoroughly titura'ted with ethyl acetate. The ethyl acetate is "decanted and dried over anhydrous sodium sulfate, filtered to remove solids, and stripped on a rotary evaporator to give a colorless oil which slowly crystallizes. A total of 35.4 g. (96 percent) of crude product is obtained which is used without further purification. 4

Preparation of the Intermediate: N-Ethyl-D-Alaninol N-Acetyl-D-Alanine (35.4 g.,- 0.270 mole) is dissolved in 350 ml. of dry tetrahydrofuran and 63 ml. of 4.2M lithium aluminum hydride in ether added dropwise with rapid stirring at a rate such that the solvent refluxesgently. After addition is complete, refluxing with rapid stirring is continued for 3 hours. After cooling the stirred mixture in an'ice bath, ml. of water is added dropwis e, followed by 20 ml. ,of percent aqueous potassium hydroxide solution, and 40 ml. of water. The precipitated solids are removed by filtration, washed with tetrahydrofuran, percolated with hot ethanol, and again filtered. The combined filtrates are dried over anhydrous sodium sulfate, and stripped of solvent. The oily residue is shaken with tetrahydrofuran and the super-natant liquid decanted, filtered, and stripped of solvent. There is obtained a yield of 15.8 g. (64 percent) of an amber oil.

Preparation of the Intermediate: D 2-lmino-3- ethyl-4-methyl-1 ,3-oxazolidine N-Ethyl -D-alaninol (17.6 g., 0.171 mole) prepared by the above-described method is dissolved in ml. of benzene. Powdered sodium hydroxide (7.1 g.) is added and rapid stirring begun. A solution of 18.1 g. of cyanogen bromide dissolved in 50 ml. of benzene is added dropwise to the above mixture which has been cooled in an ice bath. After the addition of cyanogen bromide is complete, another 1 g. of powdered sodium hydroxide is added and the whole stirred for 2 hours at room temperature. The solids are removed by filtration and the solvent removed by a rotary evaporator. There is obtained a yield of 19.0 g. (87 percent) of a wine-red oil which is vacuum flash distilled into a dry ice trap using a hot water bath EXAMPLE 14 Preparation of D 2-[N-(0,0 Dimethylphosphorothiono)-iminoI-3-ethyF4-methyl- 1,3-oxazolidine The above oxazolidine (11.5 g., 0.0898 mole) is dissolved in ml. of benzene and 3.7 g. of powdered sodium hydroxide added. 0,0-Dimethyl phosphorothionochloridate (14.5 g.,0.898 mole) is dissolved in 25 ml. of benzene and is added to the above rapidly stirred mixture. The temperature is kept below 45 by use of a water bath. After stirring for A hour at room temperature another 1 g. of powdered sodium hydroxide is added and the whole stirred for another 2 hours at room temperature. At the end of this time, water is added to the reaction mixture, the benzene layer separated and the aqueous phase is washed with benzene. The combined organic layers are washed with water, saturated sodium chloride solution, and dried over anhydrous sodium sulfate. The' solvent is removed by evaporation to yield 15.4 g. (68 percent) of an amber oil which crystallizes on standing overnight.

EXAMPLE 15 Preparation of 2-[N-(O,S-Dimethyl Phosphorothiolo)-imino]-3-ethyl-4-methyl-1,3-oxazolidine The thiono compound (8 g.) prepared by the above procedure in Example 13 is dissolved in 50 ml. of benzene, 5 ml. of methyl iodide added, and the solution refluxed for 1 hour. The solution is cooled and the solvent removed on a rotary evaporator to yield an ambe oil n l .5265.

GENERAL PROCEDURE lngeneral, the synthesis of compounds of the type r B4 lower a1koxyi N R5 P N= lower alkoxy O .4 Rs

. in and R s 3 10 or 31110). H /N P N= lower alkoxy O ,4 R7

begins by reacting a geometrically pure cis or trans isomer of a symmetrical epoxide with an appropriate primary amine to give either a threo or erythro-B- aminoalcohol. The resulting B-aminoalcohol is then allowed to react with cyanogen bromide in the presence of sodium hydroxide, to give a trans or cis-4,6-disubstituted 2-imino-l,3-oxazolidine. The oxazolidine is then phosphorylated with an appropriate phosphoryl halide in the presence of sodium hydroxide. The following example'is illustrative of the above general method.

EXAMPLE l6 Erythro-l methyl 2-ethylamino propanol To 64.3 g. of a stirred 70 percent aqueous solution of ethylamine is added dropwise 36.0 g. of trans-Z-butene oxide. The solution is allowed to stir overnight at room temperature, then at 3445 for approximately 7 hours, then again overnight at room temperature.

The resulting solution is then placed briefly on a rotary evaporator at 35 to remove unreacted ethylamine and epoxide. Ether (300 ml.) is then added and the two phase system rapidly stirred with anhydrous sodium sulfate. The ether layer is decanted and dried over anhydrous magnesium sulfate. The ether is removed on a rotary evaporator leaving 14.1 g. of a colorless liquid.

2-lmino-3-ethyl cis-4,5-dirnethyl-1,3oxazolidine To 13.6 g. of the above amino alcohol in 75 ml. of benzene is added 4.8 g. of powdered sodium hydroxide. The mixture is cooled in an ice bath and stirred rapidly during the dropwise addition of 12.3 g. of cyanogen bromide in 50 ml. of benzene. After the addition of 12.3 g. of cyanogen bromide is complete another 1.0 g. of powdered sodium hydroxide is added and the mixture stirred for 2 hours at room temperature. The mixture is filtered to remove solids and the solvent removed on a rotary evaporator to give 15.2 g. of a slightly brown mobile liquid.

2-[N-(0,0-dimethylphosphorothiono)-imino]-3- ethyl cis-4,5-dimethyl-1,3-oxazolidine To 14.8 g. of the above oxazolidine in 75 ml. benzene is added 4.2 g. of powdered sodium hydroxide. The mixture is stirred rapidly and a solution of 16.8 g. of 0,0-dimethylphosphorothionochloridate in ml. of benzene is added dropwise such that the temperature did not exceed 45". After addition of the chloridate is complete, another 0.5 g. of powdered sodium hydroxide is added and the mixture stirred for a total of 2-% hours. The solids are removed by filtration and the solution dried over anhydrous magnesium sulfate. The solvent is removed on a rotary evaporator to give 26.1 g. of the title compound a light amber oil.

GENERAL PROCEDURE The compounds of the formula are readily prepared by refluxing the corresponding thiono compounds with methyl iodide in benzene. The following example is illustrative of this general method.

EXAMPLE l7 2-[N-(O,S-dimethylphosphorothiolo)-imino]-3- ethyl-cis-4,5-dimethyl-1 ,3-oxazolidine 2-[N-(0,0-dimethylphosphorothiono)]-3-ethyl-cis- 4,5-dimethyl-l,3-oxazolidine (19.3 g.) is dissolved in ml. of benzene, 10 ml. of methyl iodide added and the whole refluxed for 1 hour. At the end of this time the solution is filtered to remove a small amount of solid and the solvent removed on a rotary evaporator to give the title compound a reddish amber oil.

EXAMPLE 18 Preparation of 2-imino-3-iso-propylperhydro-l ,3-oxazine Preparation of the Intermediate: EthylB-isopropylamino propionate To isopropylamine (63.3 g., 1.07 mole) in 300 ml. of ethanol is added'ethyl acrylate g., 1.1 mole) at 40-50 with stirring. The mixture is kept at steam bath temperature for 1 hour. The solvent is removed through a Vigreux column in vacuo and the residue is distilled. There is obtained a yield of 154.2 g. 91 percent of theory of the intermediate b.p. 68.570/6.4 mm. The IR spectrum showed the expected bands.

Preparation of the Intermediate: lsopropylainino-S- propanol To ml. of a 4.2 molar solution of lithium aluminum hydride (19 g., 0.5 mole) in ether is added 100 ml. additional dry ether. A solution of ethyl/3- isopropylaminopropionate (95.4 g., 0.6 mole) in 50 ml. of dry ether is added dropwise at l5-25. The mixture is stirred for V2 hour at room temperature and refluxed for 1 hour. 19 milliliters of water are slowly added to the mixture with stirring and cooling, followed by 19 m1. of l 5 percent sodium hydroxide solution and an additional 57 ml. of water. The mixture is stirred a few minutes, filtered, and the filter-cake extracted with ether. The ether solution is dried over magnesium sulfate and stripped in vacuo, and the residue is distilled. There is obtained a yield of 43.5 g. (74.4 percent) b.p. 6l.563/2.6 mm. theory. The IR spectrum confirmed the structure.

The above amino alcohol (35.1 g., 0.3 mole) and powdered sodium hydroxide (12.0 g., 0.3 mole) are placed in 200 ml. of dry benzene. A solution of cyanogen bromide (30.9 g., 0.3 mole) in 100 ml. of dry benzene is added with stirring at 5-15. The mixture is then stirred 1 hour at ice-bath temperature and 2 hours at room temperature. The mixture is filtered, the filtrate treated with MgSO.,, and refilt'ered, and the solvent is removed in vacuo. The residue (43.8 g.) showed a strong C E N band at 2,200 cm in the infrared. This product is mainly the uncyclized cyanamide.

38.8 g. of the uncyclized cyanamide is dissolved in 400 m1. of benzene, 6.0 g. of powdered caustic added and the mixture stirred for 5 hours. Some heat is evolved. Removal of the solvent left an oil. This is distilled twice in vacuo, the second time through a Vigreux column. The product is collected at 48-50 /0.35 mm. No C E N band was observed in the infrared spectrum.'There is obtained a yield of 17 g.

up" or melting point, 0.

16 t The following is a table of compounds representative of those embodied in the present invention. Compound numbers have been assigned to them and are used for (43.8 percent based on the cyanamide), of the title per- The other perhydro-l ,3-oxazines described herein are prepared in an analogous manner starting with the identification throughout the balance of the specifica appropriate materials as outlined herein above. 5 ti TABLE 1 1A wherein Q is -([3 X Y R1 R3 R4 hydro-1 ,3-oxazine.

Compound Number HHHHHHHHHHHHHHHHHHHHHHHH HHHHHHHHHHHHHHHHHH.

HHHHHHHHHHHHHHHHHHHHHHHH HHHHHHHHHHHHHHHHHHHHHHHHHHH HHHHH a I I HHHH HH HHHHHHHHHHHHHHH HHHHH 'nhh I III JLIIWJ HHHHHHHHHHHHIHfIIHIII mm m nmmmmmmm mmm mmm mmmmm m m mmmmm OCMHHCCCCCCCCCHHHHHHMCCO M000mmcccoounwcmcmmnfinnnnnfic 0000K w mm: 2 00H 0 i m 52553000 0 1 5.... 5 :51:55.... 56:25:55: .221 brctpvrmwv.0 0P00000000000000000000000000 00000 o S I. S 11 ns m Ne w wee chm eestwwwee fiwefi mehmfiweme sh. am wfio l fl o qm srmfimemmsk m i HHHHHHHHMHHHH ZHHHHHHHHH Znnmpmcmm np zmnm zwe mnnnnnnnnnmeem CCCCCCCCCCCCCCCCCCCCCCCC CCCnL. WC PCPHCCCDC DnnCCCCCCCCC C(nSC m wmwm mmmmbwmmmmmm? mwwww wwm mw ww wse fi nmmnnnnmmnnnnmnunnnnnnnmannnnnmmmmmmmnHHHHHHHHHHHHHH HHHnm CCCCCCCCCCCCCCCCCCCCCCCC CCCCCCCCCCCCCCCCCCCCCCCCCCCC CCCCC OOOOOOOOOOOOOOOOOOOOOOOO OOOOOOOOOOOOOOOOOOOOOOOOOOOO OOOOO 0OOOSSOOSOSOOSSOOSOSOSOS OSOOOOSSSSSSSSSSSSSSOSOSSSOO OOOOS m I i EtOCCHzS nnnnnnnunnnnunnnnnnnnnnnnnnnnnn 3a.; HHHH .HHHHHMHHHHHHHHHHHHHHCOOCHHHHHHH [I I-I I I HHCCHHIIIIHHIHHHIHHHHHHHHHHHHHH nu 00 3.3 3 1. ii; .2 3 22:? HHHHHH HHHHHHHHHHHHHHHH 000000110CCCUCGCCGCCCCC HHHHHHH nu mn 2 00mm HH s pr r 51:25:35.... i... 500. mmnnmmnnmmmm zmmmmmmm zm zmmnm mmn 0000PP00000000000000000 0000H000 m 0 v m mm mwmwo c wwmmwmww m mmwmmmmm ll v h mmvf m.h z pmstmem amfiwwmo wnnw mwem m w nnnnnnnnnnnwwwe n ennnmmnmmmmn 00000000000 pn2 nvv2 n.00000000000 TABLE I:C ntinued I Compound 7m or melting Number X Y R1 R: R; R4 R R0 R1 point, 0.

e1"; 6 "s" (EH36 6E6 6E3 H H H H 1.5560.

cur-5:011,

90 O S CHaS CHaO (7H H H H H 1.5175

CH-C=CH S CHaO CH'aO CHzCHzCHa H H H H Liquid. S CH3O CH O CHzCHzCHa H H H H Do. S 0330 CHaO 05H H H H H D0. S CHaS CH'aO C5Hn H H H H Do. S CH3O CH3O CH2CH=CC1Z H H H H Do. S CHaO CHaO CHzCH=CCl2 H H H H D0.

S CH3O CHaO OH; H H H H Do.

CH CH=C 98 O S CHaO @1130 /CH; H H H H D0- CH CH=C S S C1130 C1110 CHzCH=CClCH H H H H D0 0 S (33:48 CHaO CHzCH=CClCH; H H H H D0. S S CHaO CH O CHZCECH H H H H D0. 0 S CHaS CHaO CH2C CH H H H H D0. S S CHaO CH3O C|H9 H H H H Do. 0 S CHzS CHgO CtHn H H H H D0. S S CHzCH: CHaCHzO CH H H H H D0. 0 S CHZCHJ Has CH; H H H H DO. 0 S CHQCHBO CHaCHzO CH H H H H D0. S O CHaO CH O C H Low melting solid. 3 0 C1130 CH2CH=CH 0- O O CHaO CHQS i-C3H1 O O CHJO CHJS CHzCH=CHg O O CHzO CHaS 02 5 S O CHJO CH O i-CaHr Systemic Evaluation Test This test evaluates the systemic toxicity by root absorption and upward translocation of the candidate systemic compound. The two-spotted mite, Tetranychus urticae (Koch) and the bean aphid, Aphis fabae (Scop.), are employed in tests for systemic activity. Young pinto bean plants in the primary leaf stage are used as host plants for the two-spotted mite. The pinto bean plants are placed in bottles containing 200 ml. of the test solution and held in place with cotton plugs. Only the roots are immersed. The solutions are prepared by dissolving the compounds to be tested in a suitable solvent, usually acetone, and then diluting with distilled water. The final acetone concentration never exceeds about 1 percent. Immediately after the plants are placed in the test solution, they are infested with the test species. Mortalities are determined after 7 days. The percentage kill is determined by comparison with control plants which are placed in distilled water only. The LD-SO value is calculated using well-known procedures. LD-SO values for the two-spotted mite are found in Table II under column ZSM-SYS; and for bean aphid under column BAS.

Young nasturtium plants (Tropaeolum sp.) are used as the host plants for the bean aphid. The host plants are transplanted into 1 pound of soil that has been treated with the candidate compound. Immediately after planting in the treated soil the plants are infested with the aphids. Concentrations of toxicants in the soil ranged from 10 ppm per pound of soil downward until an LD-SO value is obtained. Mortality is recorded after 72 hours. Comparison is made with control plants placed in untreated soil.

insecticidal Evaluation Tests The following insect species are subjected to evaluation tests for insecticidal activity.

l.Housefly (HF) Musca domestica (I inn.)

2. Lygus Bug (LB) Lygus Hesperus (Knight) Aliquots of the toxicants, dissolyed in an appropriate solvent, are diluted in water containing 0.002 percent of a wetting agent, Sponto 221 (a polyoxyether of alkylated phenols blended with organic sulfonates). Test concentrations range from 0.05 percent downward to that at which 50 mortality is obtained. In the tests, for these species, 10 one-month old nymphs of the Lygus Bug are placed in a circular cardboard cage sealed on one end with cellophane and covered by a cloth netting on the other. Test concentrations for the Lygus Bug ranged from 0.05 percent downward to that at which 50 percent mortality was obtained. Each of the aqueous suspensions of the candidate compounds are sprayed onto the insects through the cloth netting by means of a hand spray gun. Percent mortality in each case is recorded after 72 hours, and the LD-50 values expressed as percent of toxicant in the aqueous spray are recorded. The results are in Table [I under Column LB.

The following procedure is used to test houseflies. A stock solution containing 0.1 percent by weight of the toxicant in an appropriate solvent is prepared. Aliquots of this solution are combined with milliliter of an acetone-peanut oil solution in a glass Petri dish and allowed to dry. The aliquots are selected to achieve desired toxicant concentration ranging from l00 mg per Petri dish to that at which 50 percent mortality was attained. The Petri dishes are placed in a circular cardboard cage, closed on the bottom with cellophane and covered on top with cloth'netting. 25 female houseflies tioned housefly test are found in Table II under Column HF.

Systemic Test: Salt-Marsh Caterpillar Estigmene acrea (Drury) Aliquots of the toxicant dissolved in appropriate solvent are diluted in water and placed in glass bottles. Concentrations of active ingredient range from ppm to that at which 50 percent mortality is obtained. Kidney beans (Phaseolus vulgaris), supported by cotton plugs, are inserted into the solution so that the roots and major portion of the stern are completely immersed. Salt-marsh caterpillar egg masses (10 to eggs) on small pieces of tissue paper are pinned to the kidney bean leaves and allowed to hatch. Mortality is recorded after 5 days and the LD-SO values are expressed as parts per million (ppm) of toxicant in the aqueous solution. The values are found in Table II under the Column SMC-Sys.

The compounds are also active against two-spotted mite (2-SM) (Tetranychus urticae (Koch.)). Lima bean plants (Phaseolus sp.) are utilized as the host plant and infested with to mites of various ages. 24 hours after infestation they are sprayed to the point of run off with aqueous suspension of the toxicant. Test concentrations range from 0.05 percent to that at which 50 percent mortality is obtained. The values obtained in this test are found in Table II under the Columns 2SM- PE and 28M -Eggs. I

The compounds are also active against bean aphid (Aphis fabae"(Scop.)) as a contact toxicant. The same test procedure as given for the two-spotted mite above is used for the bean aphids except nasturtium (Trapaeolum sp.) plants approximately 2 to 3 inches tall are used as the host plant. The LD-50 values obtained for the compounds of this invention are found in Table II under Column BA.

As previously mentioned, the herein described compounds produced in the above described manner are phytotoxic compounds which are useful and valuable in controlling various plant species. Compounds of this invention are tested as herbicides in the following manner. I

Pre-emergence herbicide test On the day preceding treatment, seeds of seven different weed species are planted in individual rows using one species per row across the width of the flat. The seeds used are hairy crabgrass (Digitaria sanguinatis (L.) Scop.), yellow foxtail (Setaria glauca (L.) Beauv.), watergrass (Echinochloa crusgalli (1..) Beauv.), wild oats (Avend fatua (L.)), redroot pigweed (Amaranthus retroflexus (L.)), Indian mustard (Brassica juncea (L.) Cross.) and curly dock (Rumex crispus (L.)). Ample seeds are planted to give about 20 to S0 seedlings per row, after emergence, depending on the size of the plants. The flats are watered after planting. The spraying solution is prepared by dissolving 50 mg. of the test compound in 3 ml. of a solvent such as acetone containing 1 percent Tween 20 polyoxy-ethylene sorbitan monolaurate) and diluting with a small amount of water. The following day each flat is sprayed at the rate of 20 pounds of the candidate compound per gallons of solution per acre. An atomizer is used to spray the solution on the soil surface. The flats are placed in a greenhouse at 80 F. and watered regularly. Two weeks later the degree of weed control is determined by comparing the amount of germination'and growth of each weed in the treated flats with weeds in several untreated control flats. The rating system is as follows:

TABLE II.INSECTICIDAL EVALUATION RESULTS; LD-50 VALUES 2-SM HF SMC Compound gJ LB BA BAS SYS PE Eggs SYS number 25+) (percent) (percent) (p.p.m.) (p.p.m.) (percent) (percent (p.p.m.)

3.0 .0003 0000 003 08 10.0 .0008 .0003 0008 3 45. 0 .0008 0008 003 .4 5. 5 .00005 00005 03 85.0 01 005 03 3. 0 40. 0 0005 .003 .003 08 40. 0 .0003 0008 .003 08 30. 0 .0005 .0005 003 1 55.0 05 03 03 10.0 7. 5 0003 0003 .0008 03 65. 0 .01 .003 .003 3.0 18.0 001 0008 003 3 14. 0 0008 0003 0003 02 90.0 .05 .01 05 10.0 100.0 .05 .05 100.0 .005 .005 .03 3.0 5. 5 0003 00008 0001 04 70.0 .03 .05 .05 10.0 15. 0 0008 .0003 0003 .2 l00.0 .05 .05 0. 0 0005 0008 0008. 1 I00. 0 .05 03 03 8 is. 0 0003 0003 0008 .1 100.0 03 05 05 10. 0 80. 0 .001 001 003 5 100. 0 03 03,. 03 5 30. 0 001 .003 .003 3 40. 0 .000 03 .03 3. 0 100. 0 .03 .05 .05 8.0 I00. 0 05 05 05 l00.0 .03 .05 .05 l00. 0 .05 .O5 .O5 I00. 0 003 005 03 10. O 400. 0 .05 .05 .05 1m. 0 003 .0008 .003 3 l00.0 .03 ,05 .O5 100. 0 .05 ,05 05 I00. 0 .03 3 ()3 5. 0 100.0 .01 .03 03 3. 0 I00. 0 .01 03 o3 3, o |00.0 .05 .05 100. 0 .003 03 100. 0 g3; a 0

TABLE II.Cntinued HF SMC (ugJ LB BA BAS SYS 25+) (percent) (percent) (p.p.m.) (p.p.m.) (percent) Compound number 3385 .0 0 0 a .00% 1 J .M w 133 .3 1

solution is sprayed on the foliage using an atomizer.

= no significant injury (O-lS percent control M slight injury (25-35 percent control) The spray concentration is 0.5 percent and the rate -H- moderate injury (5 5-65 percent control) would be approximately lbs/acre if all of the spray -H+= severe injury or death (85-100 percent control) An activity index is used to represent the total activity on all seven weed species. It is the sum of the number of plus marks, so that an activity index of 21 represents complete control of all seven weeds.

were retained on the plant and the soil, but some spray is lost so it is estimated that the application rate is approximately l2.5 lbs/acre.

Beans are used to detect defoliants and plant growth regulators. The beans are trimmed to two or three Post-emergence herbicide test Seeds of five weed species including hairy crabgrass, Plants P flat by cutting off the excess weaker P watergrass, wild Oats, Indian mustard, and curly dock several days before treatment. The treated plants are and one crop pinto beans (Phaseolus vulgaris), are P 9 'f the greenhouse care lake" planted in flats as described abo've for pre emergence avoid sprinkling the treated foliage w th water for three screening. The flats are placed in the greenhouse at days after treatment water to the 72-85 F. and watered daily with a sprinkler. About 10 means of a Slow streflm from a watermg hQSe wkmg to 14 days after planting when the primary leaves of the care not to wet the fohage' injury rates are recorded l4 days after treatment. The rating system is the same as described above for the pre-emergence test where (-H-), and

bean plant are almost fully expanded and the first trifoliate leaves are just starting to form, the plants are sprayed. The spray is prepared by weighing out 50 mg.

of the test compound, dissolving it in 5 ml. of acetone I I i are used for the different rates of mjury and control. The injury symptoms are also recorded. The Q fflt containing 1 percent Tween 20 (polyoxy-ethylene sord f l t t bitan monolaurate) and then adding 5 ml. of water. The maximum actmty m ex or Comp 8 6 con r species in the post-emergence screening test is 18 which represents the sum of the plus marks obtained with the six plant species used in the test.

The concentration of a compound of the present invention constituting an effective amount and the best mode of administration to an insect or acarid pest or its habitat may be easily determined by those skilled in the art of pest control, as exemplified by the procedures described hereinabove. As shown above, the compounds of the present invention are, also useful as preernergence or post-emergence herbicides, and can be applied in a variety of ways at various concentrations. in practice the compounds are formulated with an inert carrier utilizing methods well-known to those skilled in the art, thereby making them suitable for application as dusts, sprays, drenches and the like. The amount applied depends upon the nature of the seeds or plants to be controlled and the rate of application may vary from one to 50 lbs. per acre. One particularly advantageous way of applying the compound is as a narrow band along the row crop, straddling the row.

Various changes and modifications can be made without departing from the spirit and scope of the invention described herein as will be apparent to those skilled in the art to which it pertains. It is accordingly intended that the present invention shall only be limited by the scope of the claims.

What is claimed is: 1. A compound according to the formula wherein X is oxygen and sulfur, R, is lower alkyl, lower alkoxy, or lower alkylthio; R, is lower alkyl, lower alkoxy, lower alkylthio, chloro lower alkyl, carbethoxy methylthio, allylthio, chlorophenylthio, nitrobenzyloxy, phenyl and substituted phenoxy in which said substituents are nitro, cyano, methylthio, chloro and tert.-butyl; R is lower alkyl, benzyl, phenyl, lower alkoxy-alkyl, alkenyl having three to five carbon atoms, inclusive, chloro-alkenyl having three to four carbon atoms, inclusive, and 2-propynyl; R, is

hydrogen, lower alkyl, cyclohexyl, vinyl, R,,, R, and R,

are independently hydrogen and lower alkyl.

2. A compound of claim 1 in which R, is lower alkoxy, R, and R, are each lower alkyl, R,,, R,, and R are each hydrogen, R, is lower alkylthio, and X is oxygen.

' 3. A compound according to claim 2 in which R, is methoxy and R, is methyl, R is ethyl and R is methylthio.

4. A compound according to claim 2 in which R, is ethoxy, R, is methylthio, R,, is ethyl and R, is methyl.

5. A compound according to claim 2 in which R, is methoxy, R, methylthio, R is ethyl and R, is ethyl.

6. A compound according-to claim 2 in which R, is methoxy, R, is methylthio, R is iso-butyl and R, is methyl.

9. A compound according to claim 8 in which R, is

methoxy, R is methylthio, R is ethyl.

10. A compound according to claim 8 in which R, is methoxy, R, is methylthio, and R,, is isopropyl.

l l. A compound according to claim 8 in which R, is methoxy, R is methylthio and R,, is n-butyl.

12. A compound according to claim 8 in which R, methoxy, R, is methylthio and R, is methyl.

13. A compound of claim 1 in which X is oxygen, R, is lower alkyl, R, is lower alkylthio, R and R, are each lower alkyl, R,, R, and R are each hydrogen.

14. A compound of claim 13 in which R, is ethyl, R, methylthio, R ethyl, R, methyl.

15. A compound of claim 1 in which X is sulfur, R, and R are each lower alkoxy, R and R, are each lower alkyl, R,,, R, and R are each hydrogen.

16. A compound of claim 15 in which R, and R, are each methoxy andR, and R, are each ethyl.

17. A compound of claim 1 in which X is oxygen, R, and R are each a lower alkyl-thio, R, and R, are each lower alkyl, and R,, R, and R are each hydrogen.

18. A compound according to claim 17 in which R, and R, are each methylthio, R, is ethyl and R, is methyl.

19. A compound of claim 1 in which X is sulfur, R, and R are each lower alkoxy, R is lower alkyl, and R,, R,,, R, and R are each hydrogen.

20. A compound according to claim 19 in which R, and R are each methoxy and R,, is methyl.

21. A compound of claim 1 in which X is oxygen, R, is lower alkoxy, R is lower alkylthio, R is lower alkoxyalkyl, R, is lower alkyl and R,, R, and R are each hydrogen.

22. A compound according to claim 21 in which R, is methoxy, R is methylthio, R,, is methoxyethyl and R, is methyl.

23. A compound of claim 1 in which X is sulfur, R, is alkoxy, R, is lower alkylthio, R,, is lower alkyl, and R,, R,, R, and R are each hydrogen.

24. A compound according to claim 23 in which R, is methoxy, R is methylthio and R, is ethyl.

25. A compound of claim 1 in which X is oxygen, R, is lower alkyl, R, is lower alkylthio, R is lower alkoxyalkyl, and R, is lower alkyl and R,,, R,, and R are each hydrogen.

26. A compound according to claim 25 in which R, is ethyl, R is methylthio, R,, is methoxy ethyl, and R, is methyl.

27. A compound of claim 1 in which X is oxygen, R, 1 

1. A compound according to the formula
 2. A compound of claim 1 in which R1 is lower alkoxy, R3 and R4 are each lower alkyl, R5, R6 and R7 are each hydrogen, R2 is lower alkylthio, and X is oxygen.
 3. A compound according to claim 2 in which R1 is methoxy and R4 is methyl, R3 is ethyl and R2 is methylthio.
 4. A compound according to claim 2 in which R1 is ethoxy, R2 is methylthio, R3 is ethyl and R4 is methyl.
 5. A compound according to claim 2 in which R1 is methoxy, R2 methylthio, R3 is ethyl and R4 is ethyl.
 6. A compound according to claim 2 in which R1 is methoxy, R2 is methylthio, R3 is iso-butyl and R4 is methyl.
 7. A compound according to claim 2 in which R1 is methoxy, R2 is methylthio, R3 is isopropyl and R4 is methyl.
 8. A compound of claim 1 in which X is oxygen, R1 is lower alkoxy, R2 is lower alkylthio, R3 is lower alkyl, R4, R5, R6 and R7 are each hydrogen.
 9. A compound according to claim 8 in which R1 is methoxy, R2 is methylthio, R3 is ethyl.
 10. A compound according to claim 8 in which R1 is methoxy, R2 is methylthio, and R3 is isopropyl.
 11. A compound according to claim 8 in which R1 is methoxy, R2 is methylthio and R3 is n-butyl.
 12. A compound according to claim 8 in which R1 is methoxy, R2 is methylthio and R3 is methyl.
 13. A compound of claim 1 in which X is oxygen, R1 is lower alkyl, R2 is lower alkylthio, R3 and R4 are each lower alkyl, R5, R6 and R7 are each hydrogen.
 14. A compound of claim 13 in which R1 is ethyl, R2 methylthio, R3 ethyl, R4 methyl.
 15. A compound of claim 1 in which X is sulfur, R1 and R2 are each lower alkoxy, R3 and R4 are each lower alkyl, R5, R6 and R7 are each hydrogen.
 16. A compound of claim 15 in which R1 and R2 are each methoxy and R3 and R4 are each ethyl.
 17. A compound of claim 1 in which X is oxygen, R1 and R2 are each a lower alkyl-thio, R3 and R4 are each lower alkyl, and R5, R6 and R7 are each hydrogen.
 18. A compound according to claim 17 in which R1 and R2 are each methylthio, R3 is ethyl and R4 is methyl.
 19. A compound of claim 1 in which X is sulfur, R1 and R2 are each lower alkoxy, R3 is lower alkyl, and R4, R5, R6 and R7 are each hydrogen.
 20. A compound according to claim 19 in which R1 and R2 are each methoxy and R3 is methyl.
 21. A compound of claim 1 in which X is oxygen, R1 is lower alkoxy, R2 is lower alkylthio, R3 is lower alkoxyalkyl, R4 is lower alkyl and R5, R6 and R7 are each hydrogen.
 22. A compound according to claim 21 in which R1 is methoxy, R2 is methylthio, R3 is methoxyethyl and R4 is methyl.
 23. A compound of claim 1 in which X is sulfur, R1 is alkoxy, R2 is lower alkylthio, R3 is lower alkyl, and R4, R5, R6 and R7 are each hydrogen.
 24. A compound according to claim 23 in which R1 is methoxy, R2 is methylthio and R3 is ethyl.
 25. A compound of claim 1 in which X is oxygen, R1 is lower alkyl, R2 is lower alkylthio, R3 is lower alkoxyalkyl, and R4 is lower alkyl and R5, R6, and R7 are each hydrogen.
 26. A compound according to claim 25 in which R1 is ethyl, R2 is methylthio, R3 is methoxy ethyl, and R4 is methyl.
 27. A compound of claim 1 in which X is oxygen, R1 is lower alkoxy, R2 is lower alkylthio, R3 is alkenyl having from three to five carbon atoms, inclusive, R4 is lower alkyl and R5, R6 and R7 are each hydrogen. 